June 28, 2016

The AecLineworkCrop command can be found on the Home ribbon tab, on the Modify panel flyout, by selecting the Crop tool from the Obscure/Crop flyout. If the Crop tool is not displayed on the Obscure/Crop flyout, select the right side of the split button (down arrow icon) to deploy the flyout and choose the Crop tool. Or, with no command active, you can right click in the drawing window, and choose AEC Modify Tools > Crop from the context menu.

The AecLineworkCrop command is used to modify the extents of closed Polylines, Circles, Hatches, AEC Polygons, Mass Element Extrusions that have an embedded profile and Spaces, as well as Block References which contain any of these objects by "cropping" the original object to a boundary defined by one or more other objects. In lieu of selecting one or more objects to serve as the crop boundary, you can also specify a rectangular area by selecting its opposite corners. You will be given the option to erase any object(s) selected to define the crop boundary; the default is No, which leaves the crop boundary object(s) in the drawing file.

If you select multiple objects at the first prompt, the AecLineworkCrop command is applied to each of those independently, using the objects selected at the second prompt on each of those selected at the first prompt.
Here are some additional notes regarding the AecLineworkCrop command:

Open linework (Lines, Arcs, open Polylines) can be selected as objects to be cropped. If they extend beyond the crop boundary, they will be trimmed to it, but will remain open items of the same object types as the pre-cropped objects.

Closed objects, including Circles and closed Polylines, can be selected as objects to be cropped. If a Circle is modified by the AecLineworkCrop command, the result will be one or more closed polylines.

MText, Text, Ellipses and Ellipse Arcs cannot be selected as objects to be trimmed, but they can all be used to define the crop boundary. For MText and Text, the bounding box of the text is used as a rectangular crop boundary.

Mass Elements with a shape other than "Extrusion" and Mass Element Extrusions that have an external Profile can be selected as linework to be cropped, but will not affected by the AecLineworkCrop command. These types of Mass Elements can be selected as an object to define the crop boundary.

If a Block Reference is selected as an object to be cropped, only those nested objects within the block on which the AecLineworkCrop command works will be affected.

Attributes within a Block Reference will not be affected by the AecLineworkCrop command.

If a Block Reference is selected as linework to be cropped, it has nested elements that can be affected by the AecLineworkCrop command and it is the only instance of that Block Reference in the drawing, then the original block definition will be redefined to include the effects of the crop. If at least one instance of the Block Reference remains unaffected by the crop, then the original block definition will remain unchanged and the affected instance(s) will become instance(s) of new, anonymous block definition(s).

If a Block Reference is selected as linework to be cropped and it has multiple nested elements which can be affected by the AecLineworkCrop command, the crop will be applied to each of those elements independently.

Multi-View Blocks can be selected as linework to be cropped, but will not be affected by the command.

If the active View Block of a Multi-View Block contains linework or objects that can define a crop boundary or part of a crop boundary, it can selected as such.

Selecting an associative Hatch as linework to be cropped will result in a non-associative Hatch, regardless of whether or not the boundary of the Hatch is also selected as linework to be cropped the same AecLineworkCrop command.

Associative Spaces, Walls, Doors, Windows and Door/Window Assemblies can be selected as linework to be cropped, but will not be affected by the command. These objects can be used to define a crop boundary. Non-associative Spaces can be modified by the AecLineworkCrop command when selected as linework to be cropped.

Selecting a single line as the crop boundary will result in no change to the linework to be cropped. You will see this message at the command line: Failed to create a crop boundary from the selected objects. Selecting two lines, even if parallel, will allow a crop boundary to be calculated and applied, but the results may be unexpected.

The object(s) defining the crop boundary do not have to form a closed loop. If multiple objects are selected, they do not have to meet endpoint to endpoint, although the results may be unexpected if there is overlap or a gap.

Use a closed boundary (or a series of objects forming a closed boundary) for more predictable results.

There are object types and combinations of objects within a Block Reference that I did not test. When using the AecLineworkCrop command in a situation that you have not previously encountered, you may want to use the Mark option of the UNDO command, so that you can easily UNDO Back to the point before the command was used if you get unexpected results.

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About Me

I am an architect employed by EwingCole in its Philadelphia office, currently serving as the Design Technology Manager. In addition to using ADT/ACA and Revit on the job, I serve as a moderator in the AUGI Forums and formerly served as a facilitator for the Autodesk ADT/ACA Discussion Groups.